Implement proper scoping for "this" in arrow functions

src/parser.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/api.h"
 #include "src/ast.h"
 #include "src/bailout-reason.h"
 #include "src/base/platform/platform.h"
@@ skipping 656 matching lines @@
 }
 
 
 const AstRawString* ParserTraits::GetNextSymbol(Scanner* scanner) {
   return parser_->scanner()->NextSymbol(parser_->ast_value_factory());
 }
 
 
 Expression* ParserTraits::ThisExpression(Scope* scope, AstNodeFactory* factory,
                                          int pos) {
-  return factory->NewVariableProxy(scope->receiver(), pos);
+  return scope->NewUnresolved(factory,
+                              ast_value_factory()->this_string(),
+                              Interface::NewValue(),
+                              RelocInfo::kNoPosition,
+                              true);
 }
 
 Expression* ParserTraits::SuperReference(Scope* scope, AstNodeFactory* factory,
                                          int pos) {
   return factory->NewSuperReference(
       ThisExpression(scope, factory, pos)->AsVariableProxy(),
       pos);
 }
 
 
@@ skipping 4657 matching lines @@
     } else {
       const uc16* data = reinterpret_cast<const uc16*>(raw_string->raw_data());
       running_hash = StringHasher::ComputeRunningHash(running_hash, data,
                                                       raw_string->length());
     }
   }
 
   return running_hash;
 }
 } }  // namespace v8::internal